Safety crane hook



May 16, 1944-.V

F. J. TRUESDALE ETAL SAFETY CRANE HOOK y Filed Nov. a', 1941 PatentedMay 16, 1944 1 vHarry Kermit Fish', Follanslne,W.Y Va., assignors toNational SteelGorporaton, a'orporation of Delaware Application November8, 1941,l Serial No. 418,410

(Cl. 294-483) Q 1 Claim.

The present invention relates to improvements in safety devices forcrane or derrick hooks to prevent accidental disengagement of the loadfrom the hook.

In steel mills and other industrial environments, stationary derricksand travelling cranes move large loads from place to place. In order forthe derrick or crane hook to lift the load there rmust usually be a loadhandling device, such as chains, platforms with lifting baiis, orspecial equipment to support the objects to be lifted in such a mannerthat the hook can engage and disengage the same. All such load handlingdevices are extremely heavy and cumbersome. When the crane is loweringthe load and the load comes to rest upona support, further movement ofthe hook often disengages those parts of theload handling device engagedwith the hook catching the operator adjacent the hook unawares. Manyfatalities occur from this source when the liberated parts of the loadhandling device strike an operator.

The present invention obviates this hazard by giving the operator of thehook full control at the point at which the load handling device isreleased from the hook. The present invention provides a bar or guardfor closing the mouth of the hook. This feature alone is not new overthe prior art, but further provision is made for automatic closingmovement of this bar -and ready control of its opening movement by theoperator. The hook itself is designed so that the bar in inoperativeposition will not interfere with movement of bails and the like into andout of the hook mouth. These desiderata are achieved Without thestrength of the hook being reduced or the operating efficiency ofthecrane lowered.v

An important object of the present invention is to provide a crane hookhaving a safety feature preventing accidental'engagement of the load.

Another important object of the present invention is the provision of asafety crane hook which allows engagement with a load at all times butprevents accidental disengagement thereof.

A further important object of the present invention is the provision ofa guardv for crane hooks positively maintained in operative positionrelative rto load engaging devices engaged by the hook.

A still further object of the present invention is the provision of aguard for crane hooks which shall be out of the way in inoperativeposition.

Other objects and advantages of this invention will-become apparentfromthe following detailed description thereof, reference being had tothe accompanying drawing which constitutes part of the presentdisclosureand wherein;

Figure 1 is a view in elevation of a structure embodying the presentinvention;

Figure 2 is a. View in cross-section taken on the line II-II of Figure1; and

Figure 3 is a view in-cross-section taken on theline III-III of Figure1.

` Referring more specifically to the drawing, referencenumeral IIJdesignates generally the body portion of a hook for cranes and the likewhich I incorporates a shank I I and a hook-shaped member I2. The bodyportion at I3 defines a recess, opening in a mouth dened by lips I4 andI5. Adjacent `the shank and in the neighborhood of vthe mouth of thehook, the body portion is slotted at I6 to form legs I1. Legs II aredrilled at I'I'in a direction perpendicular to the bifurcated section.Rotatably mounted in the drill holes I1' is a pivot pin'l. Rigidlymounted on pivot pin IB and depending therefrom is a bar or guard I9.ByV rotation of pin I8, guard I9 moves between two' extreme positions.In the vertical position shown in Figure 1 in full lines, the lower endof guard I9 fits into a recess 20 in the lip I4 of the body portion ofthe hook. In its other extreme position guard I9 is received between thelegs of the slotted section Ivi, as shown in dotted lines in Figure v1.Outside legs I1 pivot pin I8 carries an operating handle or arm 2I,which is rigidly connected to the pivot pin. Movement of arm 2I from theposition shown in full lines in Figure l to the position shown in dottedlines results in movement of guard I9 between its two extreme positions.

With the hook hanging in its customary position, as shown in Figure 1,the weight of handle 2I maintains guard I9 in abutment with lip I4 atrecess 20 which `thus acts as a stop to limit movement of the guard pastoperative position. When the bail or hook engaging element of the loadhandling device is to be engaged by the hook, it may be pushedy into themouth of the hook against the'resistance presented by bar I9 due to theweight of. arm 4I. If desired the operator at the hook may `lift handle2l to withdraw guard I9 out of the way.` When disengagement of the loadhandling device from the hook is desired, handle 2| must be raised andwhen raised to its Yextreme position as shown in dotted lines in Figure1, any interference of the guard with the load handling device iseliminated because legs II of the A:bifurcated section of the bodyportion enclose the guard throughout its length. Recess 20 protects theend of the guard when the same is operative position.

Although the preferred form of the present invention is herein shown anddescribed, it will be obvious that departure therefrom Within the scopeof the invention can be readily made. The invention is, therefore, nottobe 1i mv ited by the present disclosure exbept as 'hereinafter denedby the claim.

We claim:

A safety hook for cranes and the like compris'v' ing a body portionincluding a shankgthebody portion being formed in the shape` of a hook`to dene a recess opening in amou'th',,aslotin'the' body portionpresenting I l ci, I A ta; ,pin passing through the legs and rotatablerelative thereto, a guard rigidly mounted on therpin between the legsmovable between an operative and inoperativeposition and closing themouth in operative position, an arm extending around the body portionand having rigid attachment with the pin outside, each leg, the armmaking an angle with i the guard such that the weightfof the armmaintains the guard in operative'po'sition.' and a stop lmeans limitingmovement of the guard in operative position, the arm in such positionbeing maintained out of contact with the body portion.

FREDRICK J. TRUESDALE. l HARRY KERMIT FISH.

